The 'ugly-duckling' sign in melanoma

Self skin examination is very useful for detecting melanoma. In 1985, the ABCD acronym was introduced to help people identify suspicious moles themselves.

A = Asymmetry
B = Border irregularity
C = Colour irregularity
D = Diameter > 6mm

The E was a later but very important addition.

E = Evolving (changing)

Since that time, many of us have changed the D from diameter to DIFFERENT (i.e an 'ugly-duckling' mole that looks different for any of your other moles).

A late 2017 study reported in the Journal of the American Academy of Dermatology tested the utility of just the Ugly Duckling sign versus the ABCD acronym for simulated moles in 101 adult volunteers. The ugly duckling sign demonstrated superior accuracy of melanoma recognition, and better specificity than the ABCD group.

This is a simulated study in a relatively small number of participants, but it underlines the usefulness of a very simple tool that may increase the pick-up of melanoma by all of us. We tend to teach the whole ABCDE (with D as different) but given this data, possibly using just the D on its own is easier and more effective.